The ornamental design for an ostomypatchcutter, as shown and described.
FIG. 1 is a perspective view of a front, right side and top of an ostomy patch cutter showing my new design.
FIG. 2 is an exploded perspective view showing the bottom, right side and rear view thereof, where the broken lines represent the patch of the ostomy patch cutter, which forms no part of the claimed design; and,
FIG. 3 is a top plan view thereof, where the broken lines represent a threaded member, which forms no part of the claimed design.